1. Field of the Invention
This invention relates to coupling devices, and more particularly to pipe coupling equipment especially suited for use in coupling or clamping two pipes together in an end-to-end relationship, and for forcing the pipes apart while they are being disconnected.
2. Description of the Prior Art
Coupling devices suited for clamping pipe or hose flanges together are commonly used in making fluid-tight connections in a quick, secure and safe manner between marine tanker manifolds and articulated loading arms mounted on docks or other stationary facilities. These prior art coupling devices are generally designed to work with cylindrical pipes or hoses having a radially extending flange at the end of the pipe and a cylindrical tanker manifold having a matching radially extending flange at the end thereof. The devices secure the two flanges together in a fluid-tight connection by means of clamps which vary in design from relatively simple couplers with C-type clamps to hydraulically powered couplers utilizing toggle actuated clamps. Some examples of these coupling devices are described in U.S. Pat. Nos. 2,916,789 to Hendrix; 3,473,830 to Haley; 3,489,434 to Haley; 3,586,350 to Ashton; 3,661,408 to Gibbons; and 3,830,533 to Mezei et al. These devices work quite well when connecting between a dock and a tanker anchored in a quiet harbor, but are less satisfactory in a location where there is considerable movement between the tanker and the receiving or storage facility.
With the advent of the supertanker, special problems arose in the design and use of connectors between the tanker manifold and the outboard end of marine loading arms. The reason for the special design problems is that most supertankers are too large to be unloaded at many of the existing docks and harbors. These supertankers require more space and more water depth than is available in many of the harbors. One way to alleviate this problem is to send out smaller tankers which meet and unload the supertanker on the open sea and the smaller tankers unload at the existing docks or harbors. This introduces additional problems because the large and small tankers move in relation to each other so much that it is difficult, if not impossible, to make transfer connections between the two vessels using the prior art cylindrical receiving manifolds and the cylindrical pipes at the outboard end of the marine loading arms.
One solution is to place a cone-shaped connector at the end of the receiving manifold on one tanker and a complementary cone-shaped connector at the end of the marine loading arm on the other tanker. The loading arm cone can readily be stabbed into the manifold cone to make the required connection. Flanges mounted near the ends of the cones can be clamped together to secure the cones in a fluid-tight connection. However, the use of the connecting cones introduces still another problem. The cones have a tendency to "stick together" when the fluid transfer has been completed so that it is often difficult to disconnect the connectors. What is needed is a coupling device that can clamp the cone on the loading arm to the cone of the manifold in a fluid-tight connection during fluid transfer and then force the cones apart when the transfer of fluid is completed.